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initially treated with oral agents in the hope that they will derive some benefit. Treatment failures and partial responders are further evaluated for toxin injection directed by individualized examination findings. One weakness of this study is its small sample size. Although future prospective studies with larger sample sizes are necessary, this study is the first to provide a paradigm for treatment of an often poorly controlled dis order. Prior to this series, our paradigm for EVT treat ment was formulated through the combined effort and experience of the senior author ( A . B .) and movement dis order specialists who treated approximately 80 patients with essential voice tremor between 1990 and 2005. Unfortunately, medical records for most of these patients were unavailable for review; thus, this report focuses solely on those more recently treated patients. The pro posed algorithm is based on both this current data and the cumulative experience of the senior author ( A . B .), who has treated patients with this condition for more than 20 years. Patients with concurrent dystonia were included in this series, which may cause controversy among some readers. However, we believe these two diagnoses can and often do coexist, and that distinguish ing between them is important to help guide management. CONCLUSION EVT is a common laryngeal disorder that can lead to severe functional disability. Correctly diagnosing this condition can be challenging, and other neurological dis eases can present with similar symptoms or occur con currently. Botulinum toxin therapy provides safe and effective symptom improvement and should be consid ered for patients without coexistent limb tremor, and for those who have failed oral medications. BIBLIOGRAPHY 1. Louis ED. Essential tremors: a family of neurodegenerative disorders? Arch Neurol 2009;66:1202–1208. 2. Sulica L, Louis ED. Clinical characteristics of essential voice tremor: a study of 34 cases. Laryngoscope 2010;120:516–528. 3. Elble RJ, Tremor Research Group. Report from a U.S. conference on essen tial tremor. Mov Disord 2006;21:2052–2061.

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Laryngoscope 123: October 2013

Sinclair et al.: Botulinum Toxin Injection for Essential Vocal Tremor 2501